Digital cinema projection systems are often used to display motion pictures in commercial movie theaters. Typically, such systems comprise a digital video projector and a playback server that provides digital content to the projector. In typical projection systems, this content is supplied from the server to the projector over one or more video links, such as a high-definition serial digital interface (“HD-SDI”) or digital video interface (“DVI”) connection. To prevent, or at least minimize, unauthorized access of the content, the digital content is often encrypted for transport over the one or more video links using an Advanced Encryption System (“AES”) based local link encryption system.
Many AES-based encryption systems, however, use parameters specific to particular video links to drive the encryption system. Similarly, many video links, such as HD-SDI, reserve certain codes for synchronization. Because of this, it is often difficult to transport encrypted data across different link types, as consecutively routing the data through two different link types requires that the data be decrypted and re-encrypted to each link type.